Ultra-high pressure piston pump



Oct. 18, 1966 A, J, MASClOPlNTO 3,279,391

ULTRA-HIGH PRESSURE PISTON PUMP Filed June 18, 1964 2 Sheets-Sheet l 2 Em *VW/2 INVENTOR.

Oct. 18, 1966 A. J. MAscloPlNTo 3,279,391

ULTRA-HIGH PRESSURE PIsToN PUMP Filed June 18, 1964 2 Sheets-Sheet 2INVENTOR United States Patent O 3,279,391 ULTRA-HIGH PRESSURE PISTONPUMP Anthony J. Masciopinto, Wichita, Kaus., assignor, by mesneassignments, to Electronic Communications, Inc., Wichita, Kans., acorporation of New Jersey Filed June 18, 1964, Ser. No. 377,456 8Claims. (Cl. 103-171) This invention is a continuation-in-partapplication of my co-pending application Serial No. 324,390, tiledNovember 18, 1963, for Piston Pump, now abandoned.

This invention relates to improvements in ultra-high pressure pistonpump and has for one object to provide a double acting reciprocatingpiston pump wherein the piston travel is exceedingly short and whereinthe piston can reciprocate at very high speed maintaining asubstantially continuous high pressure output.

In conventional piston pumps, high uid pressure delivery requires highinput power. This in turn makes a high pressure pump relativelyexpensive in initial cost, as well as expensive to operate.

It is a prime object of the invention to provide a piston pump whichwill discharge uid at Very high pressure, yet which requires relativelylow input power.

It is an additional object to provide a double acting high pressure pumpin which the piston is positively moved in both directions by a powerrotated eccentric cam which has direct contact with the pistonthroughout the length of both its strokes.

Other objects will appear from time to time throughout the specificationand claims.

The invention is illustrated more or less diagrammatically in theaccompanying drawings, wherein- FIGURE l is a section through the line 11 of FIG- URE 2;

FIGURE 2 is a section along the line 2-2 of FIG- URE l;

FIGURE 3 is an isometric view of the pump piston;

FIGURE 4 is a side elevation with parts in section of a modied form ofpump;

FIGURE 5 is a section along the line 5*5 of FIG- URE 4;

FIGURE 6 is a section along the line 6 6 of FIG- URE 4 with partsomitted.

Like parts are indicated by like characters throughout the specificationand drawings.

The pump body includes a central section 10, and cylinder heads 11 and12, held in place by bolts 13. Central section has a central cylindricalbore which serves as a working chamber 14 for pump piston 15, an inlet16 communicating with an inlet chamber 17, and an outlet 18communicating with an outlet or discharge chamber 19. The cylinder headsenclose at each end of the body section, uid transfer passages 20 and21, connecting respectively the inlet'chamber 17, the working chamber 14and the outlet chamber 19. Normally closed spring pressed check valves22 and 23 control intake iluid ow between inlet chamber 17 and workingchamber 14 through transfer passages 20 and 21. Normally closed springpressed check valves 24 and 25 control discharge fluid from the workingchamber 14 to outlet chamber 19 through transfer passages 20 and 21. Thecheck valves prevent back How in the usual manner.

V 3,279,391 Patented Oct. 18, 1966 Piston 15 is initially a solidcylindrical bar of metal or plastic with a transverse central bore hole26, the inner end of which centrally intersects a transverse channel orpocket 27, which is bounded by two longitudinally spaced, transverse,parallel, cam cooperating surfaces 28 and 29 which lie in planes normalto the central longitudinal axis of the piston.

The piston reciprocating mechanism includes a shaft 30 adapted to berotated by any suitable power unit, not shown. Shaft 30 extendstransversely through the transverse aperture 26, the pocket 27 in thepiston and across the working chamber and is journaled on opposite sidesof the piston in bearings 31 and 32 socketed in the central section 10.

An eccentric bushing 33 is rigidly attached to an intermediate portionof shaft 30 to rotate with it. The circular peripheral surface ofbushing 33 carries an antifriction bearing 34. The outside diameter ofthe outer race of bearing 34 is such that the race has a close working tbetween the surfaces 28 and 29 to permit the bearing race to movetransversely with respect to the piston asA the shaft rotates. The borehole 26, being considerably larger in diameter than shaft 30 allows thepiston to reciprocate freely within the stroke limits determined by thedegree of eccentricity of the cam. The eccentric cam which drives thepiston is made up of the eccentric bushing 33 and the bearing 34. Thebearing 34 is lubricated through grease tting 35 on the end of shaft 30and ducts 36 and 37 in the shaft.

In FIGURES 1 and 2 the piston 15 is shown at the upper end of itsstroke. As shaft 30 is rotated, cam 33, 34 in positive contact with thesurfaces 28 and 29 drives the piston 15 up and down. The position of thecam at the end of the down stroke is indicated by broken lines in FIGURE1.

The low power input required to operate the described pump isaccomplished through the mechanical advantage provided by the use of thecircular eccentric cam acting directly on the piston to positively moveit in both directions.

In the modified form of FIGURES 4 to 6 the cast pump body 41, centrallycylindrically apertured from top to bottom as at 42 contains cylindricalliner sleeves 43 to define upper and lower concentric, pump cylinders inthe aperture 42.

Extending through the casting from top to bottom are an inlet chamber 44and an outlet chamber 45. Cylindrical valve seats 46 are concentric withthe inlet and outlet chambers, receive respectively inlet spring loadedpoppet valve assemblies 47 at each end of inlet chamber 44 and similaroutlet valve assemblies 48 at each end of outlet chamber 45. Seal rings49 encircle the outboard sides of the valve assemblies.

The opposite ends of the cas-ting are closed by cylinder heads 50. Sealrings 49 and seal rings 51 are compressed between the cylinder heads andthe casting to make tight -seals for lthe cylinders and the inlet andoutlet chambers. The cylinder heads are held in place by cap screws 52.

Cast in the cylinder heads `are intake valve pockets 53 in register withthe intake valves 47, exhaust valve pockets 54 -in register with theexhaust valves 48 and cylinder pockets 55 each in register with and opento a pump cylinder. Ducts 56 extending across each cylinder head jointhe three pockets in each cylinder head in series. An inlet port 57 andexhaust port 58 communicate with the chambers 44 and 4S and may bethreaded to receive pipe connections in the usual manner.

The one-piece monoblock piston has an upper piston head 59 and a'lowerpiston head 60, joined by a central web 61 apertured at 62 to receivethe drive shaft 63 supported in bearings 64 on opposite sides of thepump body. The drive shaft 63 is eccentric at 65 between lthe bearings64` On both sides of the web 61 are antifriction bearings includingneedles 66 riding on the eccentric `65 in outer races 67. Wear shi-ms 68encircle the eccentric and abut the inner ends of the needles and theinner sides -of the races in opposition to retaining rings 69 whichab-ut the opposite ends of the needles and the opposite sides of theouter races.

The outer bearing races 67 are received in pockets on opposite sides ofthe piston web 61. These pockets are defined at top and *bottom byhorizontal plane cam surfaces 70, the crank faces of the piston heads,the distance between the surfaces 70 being substantially equal to theouter diameter of the outer races 67. Thus as the eccentric shaftrotates moving the outer races up and down and laterally, they remain inconstant camming contact with the surfaces 70 to impart a straight linereciprocation to the piston to cause it to pump in the usual manner.

As the piston lrnoves up, fluid is forced by piston head 59 out throughthe upper cylinder pocket 55, duct 56 and exhaust valve pockets S4 tounseat the valve 48 and force liquid into the discharge or outletchamber 45. Meanwhile the lower piston head 60y draws uid in from theintake chamber 44 through lower inlet valve 47, inlet chamber 44, duct56, cylinder pocket 55 into the lower cylinder. quences follow in theusual manner.

The diameter of the piston is large in proportion to its stroke. The twopiston heads are grooved at 71 to receive O-rings 72 in cont-act withythe liners 43. O- rings of U-shaped cross section may be used. Tworings for each piston head are usually sufficient t-o make a tightpacking.

Any suitable means, if desired a press fit, may be used for holding thebearings 64 in the pump body 41. A Zerk fitting 73 discharging into aduct 74 and -a cross duct 7S conducts lubricant into the clearance spacebetween the eccentric 65 and the aperture 62 in the web 61. As theeccentric rotates and the piston reciprocates, the clearance'between thelinner periphery of the aperture and the eccentric remainsvolumetrically constant but its position changes with the angularposition of the eccentric. Pressure through the Zerk fitting fills thisclearance and fills the clearances in the needle bearings. A weep hole80 communicates with the inner chamber defined by the clearance and thebearing to protect the system against too great grease pressure. Thecylinder liners terminate far enough away from the eccentric and theassociated parts -to provide adequate clearance as the eccentricrotates. The eccentric shaft is slotted at 76 to receive a key 77 fordrive, preferably applied to that side of .the casting opposite to theintake and exhaust ports 57 and 58.

In FIGURE 6, the bearings 64 are omitted in the interest of clarity,fitting into the socket 78, there being one -on each side of the pumpbody and the two bearings ktogether with the cylindrical walls 79 onboth sides of the pump cylinder define a lubricant chamber enclosing theeccentric and the needle bearings.

I claim:

1. In a pump, a cast metal pump body cylindrically apertured from top tobottom to define a pump chamber, a double ended one-piece piston mountedfor reciproca- As the cam shaft rotates, these se- 1 tion in the pumpchamber including upper and lower piston heads and an apertured webjoining them, a drive shaft extending through the pump body across thepump chamber and through 4the aperture in the web, bearings on oppositesides of the pump body for said shaft, eccentric driving means betweenthe shaft and the piston on both sides of the web.

2. In a pump, a cast metal pump 4body cylindrically apertured from topto bottom to define a pump chamber, a double ended one-piece -pistonmounted for reciprocation in the pump chamber including upper and lowerpiston heads and an apertured web joining them, a drive shaft extendingthrough the pump body Aacross the pump chamber and through the aperturein lthe web, bearings on opposite sides of the pump body for said shaft,eccentric driving means between the shaft and the piston on both sidesof the web,

the driving means including opposed cam surfaces on the piston on bothsides of the aperture and on both sides of the web the driving means onboth sides of the web engaging said cam surfaces and in eccentricrelationship to the shaft.

3. In a pump a c-ast metal pump body cylindrically apertured from top tobottom to define a pump chamber, a double ended one-piece piston mountedfor reciprocation in the pump chamber including upper and lower pistonheads and an apertured web joining them, a drive shaft extending throughthe pump body across the pump chamber and through the aperture in theweb, bearings on opposite sides of the pump body for said shaft,eccentric driving means between the shaft and the piston on both sidesof the web,

the radius of the aperture in the web being greater than the maximumthrow of the eccentric driving means.

4. In a pump, a cast metal pump body cylindrically apertured from top tobottom to define a pump chamber, a double ended one-piece piston mountedfor reciprocation in the pump chamber including upper and lower pistonheads and an apertured web joining them, a drive shaft extending throughthe plump body 'across the pump chamber and through the aperture in theweb, bearings on opposite sides of the pump body for said sha-ft,eccentric driving means between the shaft and the piston on both sidesof the Web,

the driving means including opposed cam surfaces on the piston on bothsides of the aperture and on both sides of the web, the driving means onboth sides of the web engaging said cam surfaces and in eccentricrelationship to the shaft,

said means including an eccentric on the shaft, needle bearings engagingthe eccentric, races enclosing the needle bearings and engaging the camsurfaces.

5. A pump including a cast met-al pump body cylindrically apertured fromend to end, cylindrical liners enclosed in said aperture at each endthereof to define upper and lower aligned concentric cyiinders, a twoheaded onepiece piston mounted for reciprocation in said cylinders, atwo-headed one-piece piston mounted for reciprocation in said cylinders,`a central web joining the piston heads, bearings removably mounted onthe pump body on opposite sides of the axis of the cylinder, aneccentric drive shaft carried by said bearings extending across the pumpbody and through the web, and the web being apertured to receive theshaft, the radius of the aperture being greater than the distance fromthe center of the shaft to the maximum excursion of the eccentric,opposed cam surfaces perpendicular to the axis of the piston on oppos'esides of the web on the under sides of the piston, anti-friction bearingmembers interposed between the eccentric shaft and the cam surfaces onopposite sides of the web.

6. The device of claim 5 characterized by the fact that saidanti-friction bearings include needle bearings on the eccentric andanti-friction bearing races encircling the 3,279,391 5 6 needles and incontact with the cam surfaces associated References Cited by theExaminer with the upper and lower piston heads. UNITED STATES PATENTS 7.The device of claim 5 characterized by the fact that the clearancebetween the aperture in the central web and gampben ow the drive shaftdenes a lubrication chamber for the 5 eaupre 2,771,037 11/1956 Johnston103-171 X needle bearings on both sides of the central web. 3 200 7598/1965 Gummi 10`3 171 X 8. The device of claim 7 characterized by thefact that a weep hole extends through the wall of the pump body FOREIGNPATENTS open to atmosphere at one end and at the other end in 672,07210/1963 Canada.

communication with the spiace between `one of the needle M ARK NEWMANPrimary Examinerbearings and the socket containing the bearings mountedon the pump body. WARREN E. COLEMAN, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3279,391 October 18 1966 Anthony J., Masciopinto It is hereby certifiedthat error appears in the above numbered patent requiring correction andthat the seid Letters Patent should read as corrected below.

Column 4 1ne Z0, after "web" insert e comme; lines 58 and 59, strike out"a two-headed one-prece piston mounted for reciprocaton in saidCy11rndersj'; 1 lne 63, strike out "and", second occurrencec Signed andsealed this 5th day of September 1967l (SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner ofPatents

1. IN A PUMP, A CAST METAL PUMP BODY CYLINDRICALLY APERTURED FROM TOP TOBOTTOM TO DEFINE A PUMP CHAMBER, A DOUBLE ENDED ONE-PIECE PISTON MOUNTEDFOR RECIPROCTION IN THE PUMP CHAMBER INCLUDING UPPER AND LOWER PISTONHEADS AND AN APERTURED WEB JOINING THEM, A DRIVE SHAFT EXTENDING THROUGHTHE PUMP BODY ACROSS THE PUMP CHAMBER AND THROUGH THE APERTURE IN THEWEB, BEARINGS ON OPPOSITE SIDES OF THE PUMP BODY FOR SAID SHAFT,ECCENTRIC DRIVING MEANS BETWEEN THE SHAFT AND THE PISTON ON BOTH SIDESOF THE WEB.